Appendix 2 - Vegetation Communities and Regional Ecosystems

2o on the sheltered slopes of Moa provides habitat for Archidendron hirsutum (Rare) and
disjunct populations of Polyalthia australis. The best development of the ecosystem is
provided on Muralug Island as VC2q where it occupies a series of rocky diorite knolls
protruding above a broad alluvial plain. The type supports restricted occurrences of
Terminalia complanata, Albizia lebbeck, Cordia myxa, Lagerstroemia archeriana and
Indigator fordii. The latter represents the highly disjunct occurrence of an extremely rare
species, previously known from only four to six trees on the southern slopes of the
McIlwraith Range.
16. Regional Ecosystem 3.12.3x1 (VC6a) is a proposed new RE, accounting for Acacia
auriculiformis open forest with vine forest understorey. This unique community is
restricted to Iama Island (VC6a) with a minor occurrence also mapped on Gebar. High
biodiversity values are given to this community given its uniqueness in the national,
regional and local contexts, and through provision of habitat for a highly disjunct
population of Luvunga monophylla (Rutaceae), being a new record for Queensland.
17. Regional Ecosystem 3.12.5x1 is proposed as a new RE recognising a unique expression
of evergreen to complex evergreen mesophyll to notophyll vine forest and thicket on
mountain ranges of Torres Strait Islands. The proposed new ecosystem represents a
diverse range of floristic and structural variations that have been previously
unrecognised. This ecosystem is extremely undersampled in regard to its botanical and
faunal diversity and warrants more detailed investigation of these components in future
studies. The likelihood of finding significant new botanical and faunal records within
this community can be regarded as extremely high.
18. Vegetation Community 5f (proposed as a component of RE3.12.18) is restricted to
Naghir Island, occupying the well-drained granitic soils of the footslope and colluvial
apron on the islands western side. This community provides Australia’s most northerly
occurrence of Eucalyptus leptophleba, and is highly significant for this reason. The
occurrence of this community is well-removed from examples on northern Cape York
Peninsula, with the only other recognised occurrence of the species in the Torres Strait
Group confined to scattered trees on Thursday Island. The taxon also occurs on the
windswept coastal dunes of Naghir (RE3.2.25) as a component of VC14t.
Whilst the signifigance of regional ecosystems can be assessed on an individual basis, the values
of the broader mosaic of vegetation across the Torres Strait Sub-region, including its complexity,
diversity and connectivity should also be considered highly significant. The study revealed 77
regional regional ecosystems in the Torres Strait study area, accounting for approximately one
third of the currently documented ecosystem diversity in the broader bioregion within a
recognised sub-region contributing less than 0.01% to the bioregions total land area
(12,050,307.0576 ha – IBRA Version 5). Of the islands represented, the diversity of the
vegetation on Moa Island which ranges from upland complex rainforests, well-developed gallery
rain forests, expansive plains with a variety of woodland, heathland, shrubland and swampland
forms, provides biodiversity values that are unlikely to be matched on any mainland conservation
area. At present, much of this landscape is free from degradation associated with invasive species
and other impacts such as development.
7.2 Summary of Flora
7.2.1 Regional Flora
An analysis of the field survey data in combination with EPA Corveg and Herbrecs data and
previous studies for the study area identifies a vascular flora of 1,330 species (Appendix B) 6 .
6
Analysis includes Herbrecs data from Albany Island which was not part of mapping area. Includes subspecies and
varieties.
3d Environmental – Torres Strait Regional Ecosystem Mapping Project – August 2008
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